Dispensing valves



0a. 28, 1969 r c. A. HOGG 3,474,940

DISPENSING VALVES Filed July 25, 1967 INVENTOR LHm sTbPHER A. HOGGATTORNEY United States Patent 3,474,940 DISPENSING VALVES Christopher A.Hogg, Redbridge, Ilford, England, assignor to The British Oxygen CompanyLimited, a British Company Filed July 25, 1967, Ser. No. 655,820 Claimspriority, application Great Britain, July 26, 1966, 33,451/ 66 Int. Cl.B6511 /72, 83/00 US. Cl. ZZZ-402.20 9 Claims ABSTRACT OF THE DISCLOSUREThis invention relates to dispensing valves, particularly for dispensingpredetermined quantities of fluid from a source of fluid under pressure.

It is known to use a manually-operated valve to control the release ofgas from a source of pressurised gas. This suffers from the disadvantagethat only coarse control is provided over the quantity of gas dispensed.

The present invention aims at providing a dispensing valve which isefiective to release a predetermined quantity of gas for each operationof the valve.

Accordingly the present invention provides a dispensing valve, which, inits broadest aspect, is as claimed in claim 1 of the appended claims.

The present invention will now be described by way of example withreference to the accompanying diagrammatic drawing, which is an axialsectional view of a valve of the present invention.

The valve is intended, on actuation, to dispense a predeterminedquantity of carbon dioxide gas under pressure from a small bulb of thetype sold under the trademark Sparklets. Referring to the drawing, a gasbulb 1 containing carbon dioxide under pressure is supported by a bulbholder 2 which is mounted on an inlet body member 3. The mouth of thebulb 1 extends into a bore of body member 3 and engages a resilientannular disc 4. Also located within the bore is a mounted piercing pin 5and an O-ring 6. The piercing pin 5 is hollow and is adapted to piercethe bulb when the bulb holder is screwed into position. The piercing pinhas a tapered end so as to seal the edges of the hole pierced in thebulb thus permitting gas to flow from the bulb only through the interiorof the piercing pin. A collar 7 holds the neck of the bulb centralduring the piercing operation. The inlet body member 3 is formed with anaxial passage 25 permitting flow of gas from the piercing pin to adischarge chamber 9 defined by the inlet member 3 and a many body 8.Disposed in passage 25 is a one-way valve having a tapering throat 10made of a suitably-resilient material, such as nylon, within which isdisposed a valve ball 11. The throat 10 is permanently sealed to theinlet member 3. A suitable difierence in pressure across the valve balltends to cause the ball to block the throat. I

The chamber 9 is in the form of a double, coaxial cylinder having aradially-extending outlet passage 12. The chamber 9 extends beyond thispassage and houses an actuator 13. The actuator 13 comprises a pushbutton 14,

3,474,940 Patented Oct. 28, 1969 a detent cam 15, a biassing cam 16, acircumferentiallygrooved forward portion 17, an O-ring seal 18 in thecircumferential groove 17 and a probe 19.

A shoulder 20 on the main body limits movement of the actuator 13 awayfrom the discharge chamber 9. In the example illustrated tworadially-extending passages 21 open into the bore of the main bodyinwardly of the shoulder 20, although only one such passage, or three ormore, could be provided. Disposed in each of these passages is a ball 22urged by a helical spring 23 against a biassing cam 16 the actuator 13.Each passage 21 is closed by a screw 24 in a screw-threaded engagementwith the wall of the passage. The balls 22, springs 23 and screw 24constitute adjustable biassing means to allow for alteration of thequantity of gas discharged for the bulb at each operation of the valve.

To enable the valve to dispense through the outlet passage apredetermined quantity of gas from the bulb, the bulb must first bepierced by the piercing pin 5 by screwing the bulb holder 2 fully ontothe inlet body member 3. The inlet valve 11, will initially be held inits closed position by pressure of gas from the bulb, so preventing flowof gas beyond the valve, and the actuating member will be in its restposition as shown, with the balls 22 engaging the biassing cam 16.Depression of the push button 14 to initiate dispensing causes theactuator to move axially towards the bulb, the balls 22 riding up the16, and the O-ring seal 18 passing the outlet passage 12 to seal thechamber 9. During this movement the springs 22 are applying a relativelysmall axial force to the actuator resisting its movement to itsoperating position.

Further axial movement of the actuator causes the balls to ride over thepeak of the cam 16 onto the detent cam 15. The spring-loaded balls thenforce the actuator inwardly to its operating position in which the probe19 unseats the ball 111 of the one-way valve. Gas under pressure thenflows into the chamber 9 and exerts a force on the face of the forwardportion 17 of the actuator 13. This force increases as the pressure ofthe gas in the chamber increases until it is sufiicient to overcome theopposing orce provide by the springs and by friction. When this happensthe actuator is moved by gas pressure away from the bulb, causing theballs 22 to ride up the detent cam 15, and down the biassing cam 16 toallow the valve ball 11 to reseat on the throat 10 to close the one-wayvalve. During the final movement of the actuator towards the shoulder 20the outlet passage 12 is unblocked, so permitting the gas under pressurein the chamber to flow through the outlet passage, until the detent cam15 again contacts the shoulder 20 in the main body to prevent furtherbackward movement of the actuator. The actuator remains in this positionuntil a further operation is initiated.

It will be noted that to initiate operation it is necessary only to movethe push button 14 until the balls 22 ride over the peak between thecams, all further movements being efiected automatically by themechanism.

Control of the quantity of fluid being dispensed may be obtained notonly by changing the volume of the chamber, or the diameter of that partof the chamber which is engaged by the O-ring seal 18 but also bappropriate choice of the axial bias applied to the actuator. Thus thecam shape may be varied as required, or more conveniently the springload on the balls can be adjusted. The quantity of fluid dispensed canthereby be increased or decreased, subject to the limiting factor thatthe gas pressure in the chamber cannot exceed the gas pressure in thebulb.

The dispensing valve may be used to dispense predetermined quantities ofthe gas under pressure in the bulb. By use of a venturi or other nozzlethis dispensed gas can entrain other gases, or flowable solids orliquids. In one application the dispensed gas is caused to entrain airin a passage in the vicinity of the heated bit of a desoldering tool.Molten solder may be sucked into this passage each time gas is dispensedby the metering valve.

In another application perfume is entrained with the dispensed gas.

In another application the dispensed gas is used directly to expel apellet or other missile from a gun barrel, and in a further applicationthe dispensed gas is used to eject a cork from a wine bottle. For thelatter application the dispensed gas is introduced into the wine bottleby a hollow needle which pierces the cork. To prevent leakage of gasfrom the wine bottle past the balls 22 when the actuator is in itsoperating position a second O-ring should be provided to seal the spacearound the actuator 13 between the outlet passage 12 and the balls 22.This modification may be used in other applications where it isnecessary to prevent leakage back through the dispensing valve of gasunder pressure in passage 12.

What is claimed is:

l. A valve for dispensing predetermined quantities of fluid from asource of fluid under pressure, comprising a discharge chamber; aone-way valve arranged when open to admit fluid under pressure into thedischarge chamber; an outlet passage leading from the discharge chamber;a longitudinally-movable actuator movable between an operating positionin which it opens the oneway valve and seals off the outlet passage, anda rest position in which it permits the one-way valve to close and opensthe outlet passage to vent the discharge chamber, means for biasing theactuator towards its rest position, and means effective only when theactuator has been displaced from its rest position, for biasing theactuator longitudinally towards its operating position, the bias beingadapted to be overcome when the pressure in the discharge chamber risessufiiciently to force the actuator towards its resting position.

2. The dispensing valve claimed in claim 1, in which the actuatorincludes a piston acting as a movable wall of the discharge chamber, andan extension from the piston which is adapted to unseat the valve memberof the one-way valve when the piston is in its operating position.

3. The dispensing valve claimed in claim 2, in which the actuatorincludes a first cam surface acted on by at least one spring-biased ballmovable transversely to the axis of movement of the actuator between aninner posi- .4 tion in which it retains the actuator in its operatingposition, and an outer position which it assumes when the actuator is inits rest position, the or each ball being cammed outwardly by the firstcam surface from its inner position by the actuator moving from itsoperating position towards its rest position.

4. The dispensing valve claimed in claim 3, in which the actuatorincludes a second cam surface adapted to be engaged alternatively by theor each ball and adapted to apply to the actuator an axial forceresisting movement of the actuator from its rest position to itsoperating position.

5. The dispensing valve claimed in 4, which the or each cam surface isfrusto-conical and is adapted to be engaged at two or more uniformlyspaced-apart points on its periphery by the biasing means.

6. The dispensing valve claimed in claim 3, in which the biasing forceon the or each ball is adjustable.

7. The dispensing valve in claim 6, in which each ball is acted on by acompression spring seated at its end remote from the ball on a memberwhich is movable axially of the path of movement of the respective ball.

8. The dispensing valve claimed in claim 2, in which the piston issealed to the wall of the discharge chamber by a first O-ring movablewith the piston and adjacent to its face.

9. The dispensing valve claimed in claim 1, in which the one-way valveis in communication with means for piercing the wall of a separablecontainer of gas under pressure.

References Cited UNITED STATES PATENTS 1,826,330 10/1931 Thiele 251-2972,016,113 10/1935 Lambert et al. 222-5 2,209,956 8/ 1940 Chase et al222-5 2,723,055 11/1955 Beard 222-40225 2,734,774 2/ 1956 Manseau222-40225 X 3,100,619 8/1963 Berghofer et al. 251-297 X ROBERT B.REEVES, Primary Examiner N. L. STACK, JR., Assistant Examiner US. Cl.X.R.

